How And When To Transplant Tomato Seedlings From Seed Tray

starting tomatoes from seed is not only cost effective but also yields healthy, tasty, and fresh produce.

So, if you want to try your hand at growing tomato from seeds you should consider transplanting your tomato plants to help your little tomato seedlings develop a healthy stem and root system. 

Now you might be wondering when to transplant tomato seedlings from seed tray into bigger pots or garden. 

Transplant your tomatoes from seed tray into their second (bigger) pots when they are 2.5 – 4 inches tall and have a set of true leaves or 2 to 3 pairs of leaves.

Transplant them in the garden when they are around 10 inches tall to ensure your seedlings have a strong root system. A good rule of thumb is to transplant when your tomato seedlings are 3 times the height of its pot.

Keep reading this post to learn more specifically about when to transplant tomato seedlings, how big should tomato seedlings be before transplanting and step-by-step instructions on how to do it, and information on how to care for your tomato plants afterwards.

Why You Should Be Transplanting Your Tomato Seedlings

• The growing season is usually not long enough to grow tomatoes from seeds completely outdoors.
• It helps your tomato plants develop a healthy root system
• It can help adjust your plants to life outdoors
• You can grow strong tomato plants via competition
• You can increase your tomato harvest

What Should You Do Before Transplant Tomato Seedlings?

Depending on where you live, it might not be possible to grow tomatoes from seeds completely outdoors. It won’t be warm enough for the plants to grow.

That is why many gardeners choose to start seeds in a seed starter kit or put them under seedling grow light.

They can grow a much greater number of plants this way and you can better control the conditions in which your plants grow.

Another way that people grow tomato plants from seeds before transplanting them to garden is sowing many seeds in one pot to foster a competitive environment.

If you start many seeds in one pot together, you know that the ones that grow tall are the strongest and most successful. 

Although it might seem like a waste of seeds because you have to cut back the smaller and less successful seedlings, it does grow strong plants that will produce good tomatoes.

Regardless of the seed starting method you use, the seed starter kit or the one pot starter, you need to transplant the seedlings in order to get some tomatoes.

When To Transplant Tomato Seedlings?

Transplanting tomato seedlings is very similar to transplanting other plants. This is the process of planting seeds or seedlings and repotting them when they grow too large.

Most seedlings develop a root system from whatever part for the plant that is under the soil.

Generally, you should plan to sow seeds 6 to 8 weeks before you plan to plant them outdoors. The specific time that you should transplant your tomato seedlings will depend on the last frost date of your home region.

A good rule of thumb for transplanting seedlings to the garden outdoors, is to wait until the temperature reaches an average of 50-55 degrees Fahrenheit at night.

You should also try to harden your tomato seedlings to the outside environment before you transplant them into the garden.

Without hardening the tomato seedlings, they are much more susceptible to issues like sun burning, wilting, windburn, and breakage.

The process of slowly introducing them to an outdoor environment will toughen them up and better equip them for life outside.

To Harden Your Tomato Seedlings, Follow These Steps

• Start to slowly introduce them to the outdoors. For the very first day, leave them somewhere they won’t get direct sun exposure for an hour or two. A place in the shade is an ideal location for a first introduction. Bring them back inside at night.
• Increase the time spent outside. In a similar location, leave the seedlings out longer each day. Still bring them inside at night.
• Increase sun exposure gradually. For the next few days put the seedlings in a place that gets northern or eastern sun exposure to get them used to direct sunlight, but not so much right away. Bring the seedlings inside every night.
• Monitor the reactions of the seedlings. Check to see if there are any signs of wilting. If they look like they are struggling, move them to a more protected area. Still, keep them indoors at night.
• Leave them outside at night when temperature reaches an overnight above 50 degrees Fahrenheit.
• Plant them in the garden. After a week or so of hardening, your tomato seedlings are ready to be transplanted!

How Big Should Tomato Seedlings Be Before Transplanting?

When transplanting seedlings, you have to do it when they are the right size.

If you wait too long, they will grow too large for the pot they are in and their roots will start to grow to the very edge of the container. This can lead to yellowing of the leaves when they are full grown.

Your tomato seedlings should be between 2-4 inches before you transplant them from seed tray into a larger pot, or if the weather permits, outside in the garden. If you want to be extra careful about helping tomato seedlings prepare for life in the garden, you can transplant twice.

They require a well-developed root system and they might not always have one when they are just 2 inches tall.

You should transplant your tomato seedlings in a larger pot when they reach 2 to 4 inches and then when they grow to 10 inches or so, they transplant them again into the garden.

How To Transplant Tomato Seedlings To Bigger Pot?

If you started your seeds in a seed starter kit or a seed tray, you will likely need to transplant them into a larger pot before they can go into the garden. This will ensure that they have a healthy root system before going outside. 

When Your Seedlings Are Ready To Go A Larger Pot, Follow These Steps To Successfully Give Them A New Home

• Get a container that is at least twice the size of the current container or seed starter that the seedling is in.
• Water the seedlings well before you plan to transplant them, as moist soil tends to stick to the roots and can cause root rot. However, you still want the soil to be a bit moist because it will help the plant adjust to a new pot.
• Lift the seedlings out of the container with a knife, and if necessary, lift them by the leaves. If you lift by the stem, you can damage the plant. Leaves grow back but stems don’t.
• Plant the seedling in the new container up to the first set of leaves. Anything that is planted under the soil will grow roots. 
• Water the seedling gently. If you don’t water right away the plant may get stressed out and start to wilt.
• Fertilize the plant once a week as directed by the fertilizer brand you use.

When they grow larger in their new pots, you can leave them in the pots for the season (if it is big enough) and harvest tomatoes that way.

Or, you can transplant them a second time into the garden if you have the space, soil, and right sunlight.

How To Transplant Tomato Seedlings To The Garden?

So, you’re finally ready to plant the tomato seedlings outdoors. make sure that you’ve hardened them so they can tolerate 6-8 hours of sun and sometimes harsh outdoor environments.

When you are ready, try to pick a day that is overcast and slightly cooler than normal for transplanting to the garden. This will help not to stress out the tomato seedlings.

Follow These Steps To Transplant Your Seedlings To The Garden

• Water the seedlings well before you plan to transplant them, as moist soil tends to stick to the roots and can cause root rot. However, you still want the soil to be a bit moist because it will help the plant adjust to a new pot.
• Lift the seedlings out of the container with a knife, and if necessary, lift them by the leaves. If you lift by the stem, you can damage the plant. Leaves grow back but stems don’t.
• Plant the seedling in the garden up to the second set of leaves. Anything that is planted under the soil will grow roots.  If your seedling has lots of foliage, you can take off the bottom leaves a day or two before transplanting (to give the stem time to heal) and then place them deeper into the soil.
• Keep all tomato plants separated. Keep them at least 30-60 inches apart. This may look strange at first but the tomatoes need room to grow their roots and collect nutrients!
• Water the seedling gently. If you don’t water right away the plant may get stressed out and start to wilt.
• Fertilize the growing tomato plant as directed by the fertilizer brand you use.
• Place the cages right after transplanting even if they don’t need the support yet. This will keep you from damaging roots later in the season.
• Mulch the garden bed.

How Do You Care For Tomato Seedlings After Transplanting Them Into The Garden?

Now that you have planted the seedlings into the garden, they need lots of care. Look after them just as you did before transplanting and monitor how they handle life outdoors.

Here are some tips to make sure that you get the most out of your plants:

• Stake the plant right after planting so that you don’t disturb the roots again. This goes for a label with the name of the plant and for any kind of cage you might use.
• Give them lots of water right after transplanting so they don’t freak out.
• Check the plants daily and give them water regularly to make sure that they are happy and healthy.
• Water them in the morning as opposed to in the afternoon or evening. This provides the plants with enough moisture to make it through hot summer days.
• Fertilize or side dress the plant with compost every couple weeks once the plants start fruiting. This will help you get larger fruits and a more bountiful harvest. The more nutrients your plants get the better the fruits will be.
• As the plant continues to grow, trim the leaves around the soil. This can prevent diseases from arising in the plants.

Regardless of the method you use (transplanting once or twice), mother nature is very resilient and forgiving.

As long as you care for your tomato seedlings and give them what they need, you will get some tomatoes. Monitor their progress and keep them happy. Don’t be afraid to experiment!